From ce352c000cb5b952d84f2f950cb549eef48978c6 Mon Sep 17 00:00:00 2001
From: Alek Ratzloff <alekratz@gmail.com>
Date: Wed, 4 Mar 2020 14:37:00 -0500
Subject: [PATCH] Add IVT register and interrupt module

Signed-off-by: Alek Ratzloff <alekratz@gmail.com>
---
 src/libvm/src/interrupt.rs     | 19 +++++++++
 src/libvm/src/lib.rs           |  1 +
 src/libvm/src/obj/syn/lexer.l  |  1 +
 src/libvm/src/obj/syn/parser.y |  1 +
 src/libvm/src/reg.rs           | 71 ++++++++++++++++++----------------
 5 files changed, 59 insertions(+), 34 deletions(-)
 create mode 100644 src/libvm/src/interrupt.rs

diff --git a/src/libvm/src/interrupt.rs b/src/libvm/src/interrupt.rs
new file mode 100644
index 0000000..aa92f3c
--- /dev/null
+++ b/src/libvm/src/interrupt.rs
@@ -0,0 +1,19 @@
+macro_rules! interrupts {
+    {
+        $($variant:ident = $value:expr),* $(,)?
+    } => {
+        pub type IntVec = u8;
+
+        $(
+            #[allow(dead_code)]
+            pub const $variant: IntVec = $value;
+        )*
+    };
+}
+
+interrupts! {
+    DIVIDE_BY_ZERO = 0,
+    INVALID_OPCODE = 1,
+    ILLEGAL_MEMORY_ADDRESS = 2,
+    HARDWARE_EVENT = 3,
+}
diff --git a/src/libvm/src/lib.rs b/src/libvm/src/lib.rs
index 731a6a7..9c3b2d3 100644
--- a/src/libvm/src/lib.rs
+++ b/src/libvm/src/lib.rs
@@ -4,6 +4,7 @@ pub mod addr;
 pub mod error;
 pub mod flags;
 pub mod inst;
+pub mod interrupt;
 pub mod mem;
 pub mod obj;
 pub mod reg;
diff --git a/src/libvm/src/obj/syn/lexer.l b/src/libvm/src/obj/syn/lexer.l
index 1f1c497..fd75e52 100644
--- a/src/libvm/src/obj/syn/lexer.l
+++ b/src/libvm/src/obj/syn/lexer.l
@@ -60,6 +60,7 @@ dump                                "DUMP"
 %fp                                 "REG_FP"
 %flags                              "REG_FLAGS"
 %null                               "REG_NULL"
+%ivt                                "REG_IVT"
 %status                             "REG_STATUS"
 %r[0-9]{1,2}                        "REG_GENERAL"
 [a-zA-Z_][a-zA-Z0-9_]*              "NAME"
diff --git a/src/libvm/src/obj/syn/parser.y b/src/libvm/src/obj/syn/parser.y
index dff3d4c..3f6c4a7 100644
--- a/src/libvm/src/obj/syn/parser.y
+++ b/src/libvm/src/obj/syn/parser.y
@@ -137,6 +137,7 @@ Reg -> Reg:
     | 'REG_FP' { FP }
     | 'REG_FLAGS' { FLAGS }
     | 'REG_NULL' { NULL }
+    | 'REG_IVT' { IVT }
     | 'REG_STATUS' { STATUS }
     | 'REG_GENERAL' {
         let v = $1.expect("could not parse reg");
diff --git a/src/libvm/src/reg.rs b/src/libvm/src/reg.rs
index 5edd911..b9eff86 100644
--- a/src/libvm/src/reg.rs
+++ b/src/libvm/src/reg.rs
@@ -36,41 +36,44 @@ registers! {
     // Zero
     NULL = 4,
 
-    // General status code
-    STATUS = 5,
+    // Interrupt vector table pointer
+    IVT = 5,
 
-    R00 = 6,
-    R01 = 7,
-    R02 = 8,
-    R03 = 9,
-    R04 = 10,
-    R05 = 11,
-    R06 = 12,
-    R07 = 13,
-    R08 = 14,
-    R09 = 15,
-    R10 = 16,
-    R11 = 17,
-    R12 = 18,
-    R13 = 19,
-    R14 = 20,
-    R15 = 21,
-    R16 = 22,
-    R17 = 23,
-    R18 = 24,
-    R19 = 25,
-    R20 = 26,
-    R21 = 27,
-    R22 = 28,
-    R23 = 29,
-    R24 = 30,
-    R25 = 31,
-    R26 = 32,
-    R27 = 33,
-    R28 = 34,
-    R29 = 35,
-    R30 = 36,
-    R31 = 37,
+    // General status code
+    STATUS = 6,
+
+    R00 = 7,
+    R01 = 8,
+    R02 = 9,
+    R03 = 10,
+    R04 = 11,
+    R05 = 12,
+    R06 = 13,
+    R07 = 14,
+    R08 = 15,
+    R09 = 16,
+    R10 = 17,
+    R11 = 18,
+    R12 = 19,
+    R13 = 20,
+    R14 = 21,
+    R15 = 22,
+    R16 = 23,
+    R17 = 24,
+    R18 = 25,
+    R19 = 26,
+    R20 = 27,
+    R21 = 28,
+    R22 = 29,
+    R23 = 30,
+    R24 = 31,
+    R25 = 32,
+    R26 = 33,
+    R27 = 34,
+    R28 = 35,
+    R29 = 36,
+    R30 = 37,
+    R31 = 38,
 }
 
 pub const LAST_REG: Reg = 63;